Energy-Optimal Scheduling in Low Duty Cycle Sensor Networks

Energy consumption of a wireless sensor node mainly depends on the amount of time the node spends in each of the high power active (e.g., transmit, receive) and low power sleep modes. It has been well established that in order to prolong node's lifetime the duty-cycle of the node should be low. However, low power sleep modes usually have low current draw but high energy cost while switching to the active mode with a higher current draw. In this work, we investigate a MaxWeightlike opportunistic sleep-active scheduling algorithm that takes into account time- varying channel and traffic conditions. We show that our algorithm is energy optimal in the sense that the proposed ESS algorithm can achieve an energy consumption which is arbitrarily close to the global minimum solution. Simulation studies are provided to confirm the theoretical results

New capacity allocation policies in revenue management

In this dissertation, we study three emerging problems in revenue management. First problem is about optimal capacity allocation in single-leg airline revenue management with overbooking. We propose new static and dynamic models. The static problems are difficult to solve optimally. Therefore, we introduce approximate models, which provide upper and lower bounds on the optimal expected revenues. In the dynamic case, we propose a model based on two streams of events; the arrivals of booking requests and cancellations. Following the characterization of the optimal policy, we also present the nested structure of the optimal allocations. Second problem is about optimal capacity allocation in the presence of a contingent commitment option. This option has been recently offered by airline systems to provide purchase flexibility to the customers. The problem becomes finding the revenue maximizing policy for contingent commitments and advance bookings. We first propose a dynamic programming model. Since it is computationally intractable, we develop an alternate dynamic model based on geometric approximation. In our numerical study, we investigate the effect of the commitment option on various test instances. In the third problem, we investigate optimal room allocation policies in hotel revenue management. Long-term stays are very common in hotel industry. Therefore, it is crucial to consider allocation of multiple-day capacities when responding to a request. This requirement leads to solving large-scale network problems, which are computationally challenging. Therefore, we work on various decomposition methods to find reservation policies for walk-in and stay-over customers. We also devise solution algorithms to solve large problems efficiently

Anxiety, motivation, stress levels and associated factors among university students in the COVID-19 pandemic

BACKGROUND/AIMS: The global coronavirus disease (COVID-19) pandemic affects society seriously in terms of psychosocial aspects, but this effect is more intense on some specific population groups. University students are among the most affected population groups by the pandemic. This study was conducted to determine the anxiety, motivation, stress levels, and associated factors among health science students during the COVID-19 pandemic. MATERIALS AND METHODS: The population of this descriptive and cross-sectional study consisted of students studying at health-related departments in three universities in Turkey. The data were collected from 855 students determined by the stratified sampling method using the online survey method. A questionnaire developed by the researchers and the Beck Anxiety Inventory (BAI) were used to collect the data. Percentage, mean, standard deviation, t-test, One-Way ANOVA test, Pearson correlation, and linear regression analysis were performed to evaluate the data. RESULTS: The results revealed that the mean age of the students was 20.85±2.37 years (min: 18; max: 41), 80.5% were women, 38.0% were nursing students, 13.7% had a family member with the diagnosis of COVID-19. The BAI mean score was found to be 29.00±7.8. According to the multiple linear regression analysis, the factors affecting students’ anxiety scores significantly were being female, impaired sleep and nutrition patterns, decreased motivation, increased stress level and having a family member with the diagnosis of COVID-19. CONCLUSION: Health science students experience severe anxiety due to COVID-19 pandemic and have moderate motivation and stress scores. Being a woman, having impaired sleep and nutrition patterns, reduced motivation, increased stress level and a family member diagnosed with COVID-19 are factors influencing the level of anxiety

New models for single leg airline revenue management with overbooking, no-shows, and cancellations

Airline revenue management (ARM) problem focuses on finding a seat allocation policy, which results in the maximum profit. Overbooking has been receiving significant attention in ARM over the years, since a major loss in revenue results from cancellations and no-shows. Basically, overbooking problem aims at maximizing the profit by minimizing the number of vacant seats. However, this problem is difficult to handle due to the demand and cancellation uncertainties and the size of the problem. In this study, we propose new models for the static and the dynamic overbooking problems. Due to the complex analytical form of the overbooking problem, in the static case we introduce models that give upper and lower bounds on the optimal expected profit. In the dynamic case, however, we propose a new dynamic programming model, which is based on two streams of arrivals; one for booking and the other one is for cancellation. This approach allows us to come up with a computationally tractable model. We also present numerical results to show the effectiveness of our models

Single-leg airline revenue management with overbooking

Airline revenue management is about identifying the maximum revenue seat allocation policies. Since a major loss in revenue results from cancellations and no-show passengers, over the years overbooking has received a significant attention in the literature. In this study, we propose new models for static and dynamic single-leg overbooking problems. In the static case, we introduce computationally tractable models that give upper and lower bounds for the optimal expected revenue. In the dynamic case, we propose a new dynamic programming model, which is based on two streams of arrivals. The first stream corresponds to the booking requests and the second stream represents the cancellations. We also conduct simulation experiments to illustrate the proposed models and the solution methods

Neoliberal politikalar çerçevesinde hasta tedavi meliyetlerinin değerlendirilmesi: 2000-2007 yılları arasında kamu eğitim ve araştırma hastaneleri üzerine bir araştırma

Anahtar Kelimeler : Neoliberal Politikalar, Küresellesme, Saglık Politikaları, HastaneHarcamaları, Hasta Tedavi Maliyetleri.ÖZETTüm dünyada uygulaması yaygınlasan neoliberal politikalar, ülkemizde de etkisini1980’li yıllardan sonra göstermeye baslamıstır. Neoliberal düsüncenin hakim ekonomipolitikaları; özellestirme, deregülasyon veya kuralsızlastırma, ticaretin serbestlesmesi,bagımsız denetleyici kurumların olusturulması, sermaye hareketlerinin serbest bırakılması,“siskin rezerv politikası” ve “faiz dısı fazla verilmesi” politikalarıdır.Neoliberal politikalar, ülkemizde basta hizmetler sektörü olmak üzere tümsektörlerle birlikte saglık sektörünü de etkiledigi gözlemlenmektedir. Ülkemizde SaglıkBakanlıgı tarafından 2000’li yıllardan sonra saglık sektöründe reform sayılabilecek önemliuygulamalar baslatılmıstır. Neoliberal politikalar, saglık sektöründe özellikle “özellestirme”,“özerklesme”, “desantralizasyon”, “aile hekimligi” ve “genel saglık sigortası” uygulamaları ileetkisini göstermektedir.Türkiye’de uygulanan neoliberal politikaların, Türkiye’deki hastanelerin %60’ındanfazlasını olusturan kamu hastanelerinde yatarak tedavi gören hastaların tedavi maliyetlerinine sekilde etkilediginin kesfedilmesi amacıyla çalısmaya baslanmıstır. Bu çerçevede kamuhastanelerindeki tedavi edici hizmetlerin, harcama kalemlerine göre ve kendi içlerindekidegisimleri; Dr. Lütfi Kırdar Kartal Egitim ve Arastırma Hastanesi ile Sisli Etfal Egitim veArastırma Hastanesi’nde 2000 yılı ile 2007 yılları arasında tedavi görmüs 7253 adet yatanhasta faturasında incelenmistir. Bu amaçla yatan hasta faturaları; yatak, laboratuar, ilaç, tıbbimalzeme, radyolojik tetkik ve genel hizmet olarak harcama kalemlerine ayrılarak fiyat, islemadedi, islem bası maliyeti ve toplam fatura içindeki oranının tek tek yıllar bazında ve 2000-2003 yılları bir dönem, 2004-2007 yılları bir dönem olarak kabul edilerek yine aynı harcamakalemlerine sınıflanmıs yıllara göre ayrılarak fiyat, islem adedi, islem bası maliyeti ve toplamfatura içindeki oranı dönemlere göre karsılastırılmıstır.Neoliberal politikaların saglık sektöründe her ne kadar saglık harcamalarını artırdıgıyönünde görüsler varsa da bu çalısmada genel olarak fiyatlarda meydana gelen artıstanziyade hizmet üretimi için gerekli ilaç malzeme ve istenen tetkik sayısında artıs görülmüstür.Arastırmada sınıflanmıs yıllara göre harcama kalemleri degerlendirildiginde; tüm harcamakalemlerinde, 2004-2007 yıllarındaki islem bası maliyetlerin 2000-2003 yıllarına göre artısgösterdigi görülmüstür. Bu artıs genel hizmet islem bası maliyetinde yaklasık %300 oranındave fatura basına islem bası maliyetinde %400’den fazla oranda gerçeklesmistir. GENERAL KNOWLEDGEName and Surname : Nursen AYDINField : ManagementProgramme : International ManagementSupervisor : Doç. Dr. Refika BAKOGLU DELORMANDegree Awarded and Date : Master Degree – 2008Keywords : Neoliberal Politics, Globalization, Health Policies, HospitalExpenses, Patient Treatment ExpensesABSTRACTThe application of neoliberal politics that began to spread all over the world, startedshowing its effect in our country after the 1980s. The economical policies that guide theneoliberal way of thinking are; privatization, deregulation and the lack of rules, theliberalization of commerce, the formation of independent supervisory institutes, the exempt ofcapital movements, the “inflated reserves policy” and the “giving over the interest rate” policy.It has been noticed so far that neoliberal policies, mainly affected the service sectorand especially the health sector. After 2000, important reforms started to be applied by theMinistry of Health in our country. Neoliberal policies are applied especially in “privatization”,“autonomy”, “decentralization”, “family medicine” and “general health insurance”.The neoliberal policies applied in Turkey, started to be applied in order to find outthe treatment costs of the patients in public hospitals, which represent 60% of the hospitals inTurkey. In these conditions, the treatment services given in public hospitals and the changesin these services and in treatment expenses were analyzed from the 7253 invoices of thepatients that were treated at Lütfi Kırdar Educational and Research Hospital and Sisli EtfalEducational and Research Hospital between years 2000 and 2007. The invoices of thepatients were separated into: bed, laboratory, medicines, medical materials, radiologicstudies and general services and respectively into: price, procedure numbers, costs perprocedure, and the percentage of each costs in the invoices, the years analyzed being 2000-2003 for one period and 2004-2007 as a second period. The expenses were separated into:price, procedure numbers, costs per procedure, and the percentage of each costs in theinvoices between the two periods were compared.Even though there are opinions on the fact that the neoliberal policy has increasedthe expenses in the health sector, in this case study the increase has been more visual in themedicines and materials used and in the number of investigations, more than the increase ofthe prices. Evaluating the expense items that were analyzed in the case study by years, thecosts per procedure between 2004-2007 increased compared to the other period 2000-2003.The percentage of this rise was of 300% per procedure and of 400% per procedure for eachinvoice

Neoliberal politikalar çerçevesinde hasta tedavi meliyetlerinin değerlendirilmesi: 2000-2007 yılları arasında kamu eğitim ve araştırma hastaneleri üzerine bir araştırma

Anahtar Kelimeler : Neoliberal Politikalar, Küresellesme, Saglık Politikaları, Hastane Harcamaları, Hasta Tedavi Maliyetleri. Tüm dünyada uygulaması yaygınlasan neoliberal politikalar, ülkemizde de etkisini 1980’li yıllardan sonra göstermeye baslamıstır. Neoliberal düsüncenin hakim ekonomi politikaları; özellestirme, deregülasyon veya kuralsızlastırma, ticaretin serbestlesmesi, bagımsız denetleyici kurumların olusturulması, sermaye hareketlerinin serbest bırakılması, “siskin rezerv politikası” ve “faiz dısı fazla verilmesi” politikalarıdır. Neoliberal politikalar, ülkemizde basta hizmetler sektörü olmak üzere tüm sektörlerle birlikte saglık sektörünü de etkiledigi gözlemlenmektedir. Ülkemizde Saglık Bakanlıgı tarafından 2000’li yıllardan sonra saglık sektöründe reform sayılabilecek önemli uygulamalar baslatılmıstır. Neoliberal politikalar, saglık sektöründe özellikle “özellestirme”, “özerklesme”, “desantralizasyon”, “aile hekimligi” ve “genel saglık sigortası” uygulamaları ile etkisini göstermektedir. Türkiye’de uygulanan neoliberal politikaların, Türkiye’deki hastanelerin %60’ından fazlasını olusturan kamu hastanelerinde yatarak tedavi gören hastaların tedavi maliyetlerini ne sekilde etkilediginin kesfedilmesi amacıyla çalısmaya baslanmıstır. Bu çerçevede kamu hastanelerindeki tedavi edici hizmetlerin, harcama kalemlerine göre ve kendi içlerindeki degisimleri; Dr. Lütfi Kırdar Kartal Egitim ve Arastırma Hastanesi ile Sisli Etfal Egitim ve Arastırma Hastanesi’nde 2000 yılı ile 2007 yılları arasında tedavi görmüs 7253 adet yatan hasta faturasında incelenmistir. Bu amaçla yatan hasta faturaları; yatak, laboratuar, ilaç, tıbbi malzeme, radyolojik tetkik ve genel hizmet olarak harcama kalemlerine ayrılarak fiyat, islem adedi, islem bası maliyeti ve toplam fatura içindeki oranının tek tek yıllar bazında ve 2000- 2003 yılları bir dönem, 2004-2007 yılları bir dönem olarak kabul edilerek yine aynı harcama kalemlerine sınıflanmıs yıllara göre ayrılarak fiyat, islem adedi, islem bası maliyeti ve toplam fatura içindeki oranı dönemlere göre karsılastırılmıstır. Neoliberal politikaların saglık sektöründe her ne kadar saglık harcamalarını artırdıgı yönünde görüsler varsa da bu çalısmada genel olarak fiyatlarda meydana gelen artıstan ziyade hizmet üretimi için gerekli ilaç malzeme ve istenen tetkik sayısında artıs görülmüstür. Arastırmada sınıflanmıs yıllara göre harcama kalemleri degerlendirildiginde; tüm harcama kalemlerinde, 2004-2007 yıllarındaki islem bası maliyetlerin 2000-2003 yıllarına göre artıs gösterdigi görülmüstür. Bu artıs genel hizmet islem bası maliyetinde yaklasık %300 oranında ve fatura basına islem bası maliyetinde %400’den fazla oranda gerçeklesmistir. GENERAL KNOWLEDGE Name and Surname : Nursen AYDIN Field : Management Programme : International Management Supervisor : Doç. Dr. Refika BAKOGLU DEL_x005F_x0003_ORMAN Degree Awarded and Date : Master Degree – 2008 Keywords : Neoliberal Politics, Globalization, Health Policies, Hospital Expenses, Patient Treatment Expenses ABSTRACT The application of neoliberal politics that began to spread all over the world, started showing its effect in our country after the 1980s. The economical policies that guide the neoliberal way of thinking are; privatization, deregulation and the lack of rules, the liberalization of commerce, the formation of independent supervisory institutes, the exempt of capital movements, the “inflated reserves policy” and the “giving over the interest rate” policy. It has been noticed so far that neoliberal policies, mainly affected the service sector and especially the health sector. After 2000, important reforms started to be applied by the Ministry of Health in our country. Neoliberal policies are applied especially in “privatization”, “autonomy”, “decentralization”, “family medicine” and “general health insurance”. The neoliberal policies applied in Turkey, started to be applied in order to find out the treatment costs of the patients in public hospitals, which represent 60% of the hospitals in Turkey. In these conditions, the treatment services given in public hospitals and the changes in these services and in treatment expenses were analyzed from the 7253 invoices of the patients that were treated at Lütfi Kırdar Educational and Research Hospital and Sisli Etfal Educational and Research Hospital between years 2000 and 2007. The invoices of the patients were separated into: bed, laboratory, medicines, medical materials, radiologic studies and general services and respectively into: price, procedure numbers, costs per procedure, and the percentage of each costs in the invoices, the years analyzed being 2000- 2003 for one period and 2004-2007 as a second period. The expenses were separated into: price, procedure numbers, costs per procedure, and the percentage of each costs in the invoices between the two periods were compared. Even though there are opinions on the fact that the neoliberal policy has increased the expenses in the health sector, in this case study the increase has been more visual in the medicines and materials used and in the number of investigations, more than the increase of the prices. Evaluating the expense items that were analyzed in the case study by years, the costs per procedure between 2004-2007 increased compared to the other period 2000-2003. The percentage of this rise was of 300% per procedure and of 400% per procedure for each invoice

Historical Perspective on the Health Transformation in Turkey

Turkey has undertaken major reforms since 2003 to transform and improve its healthcare system and health outcomes. This historical evaluation aims to shares experiences gained from Turkey’s Health Transformation Program (HTP) with scholars, policymakers, and the public. Until today from the establishment of the Republic of Turkey, the legal regulations and practices for improving health services have been explained, and the results have been evaluated from a historical perspective. Our review shows that HTP has created a model that achieved goals for universal health insurance, family medicine, access to health services, and service quality. HTP increased access to health services and affected service quality. However, it has not achieved full decentralization of secondary and tertiary healthcare providers. Public hospital associations and public health directorates were reunited under the Provincial Health Directorate. It is stated that various factors such as having three different bodies in administration, problems with the competence of appointed managers, unsettled organizational structure, more than one managers being appointed and frequent changes in office, dissatisfaction of healthcare workers, and problems in communication and coordination. Countries wishing to reform may be more productive in implementing decentralization considering in their own circumstances

Kamu sağlık kurumları çalışanlarında yardımlaşma kültürü: İstanbul il sağlık müdürlüğü ve Anadolu Güney Kamu Hastane birliği üzerine bir çalışma

Kamu Sağlık Kurumları Çalışanlarında Yardımlaşma Kültürü: İstanbul İl Sağlık Müdürlüğü ve Anadolu Güney Kamu Hastane Birliği Amaç: Sağlık kurumları çalışanlarının örgüt ve yardımlaşma kültürü düzeyini ölçmek, yardımlaşma özniteliklerini belirlemek, kurumlararası karşılaştırma yapmak ve ağ organizasyonu bakış açısıyla değerlendirmek. Gereç ve Yöntem: Araştırmaya; İstanbul İl Sağlık Müdürlüğü, İstanbul Anadolu Güney Kamu Hastaneler Birliği ve Dr. Lütfi Kırdar Eğitim ve Araştırma Hastanesi’nden 751 kişi dâhildir. Bu üç kurum, İstanbul’da sağlık hizmeti sunumunda fonksiyonları itibariyle farklı kademelerde yer almaları ve aynı zamanda birbirini bütünleyen kurumlar olmaları nedeniyle araştırma kapsamına alınmıştır. Araştırmada odak gurup görüşmesi, anket ve mülakat yöntemleri kullanılmıştır. Sosyal ağ analizi kapsamında çalışanların, yardım talep ettikleri 5 kişi ve yardım talep etmedikleri bir kişi ismi istenerek, bu kişilerin yardımlaşma öznitelikleri olan yetkinlik, erişilebilirlik, güven, samimiyet ve tanışma süresi değişkenleri değerlendirilmiştir. Bulgular: Sağlık kurumları çalışanlarının örgüt ve yardımlaşma kültürü düzeyi belirlenmiştir. Yardımlaşma öznitelikleri ortalamaları, yardım talep edilen çalışanlarda, yardım talep edilmeyen çalışanlardan daha yüksek çıkmıştır. Yardım talep edilen çalışanlarda, güven en yüksek puanı almış, yetkinlik ise en düşük puanı almıştır. Yardımlaşmadan kaçınma eğilimi, lise mezunu, 45 yaş ve üstü olan ve mevcut kurumda ve mevcut pozisyonda 21 yıl ve üstü çalışanlarda daha yüksek çıkmıştır. Sağlık kurumları çalışanlarının SAA değişkenleri yaş, eğitim seviyesi ve çalışma yıllarına göre benzerlikler göstermektedir. Sonuçlar: Araştırma sonucunda; örgüt kültürü ölçeğinde, piyasa, klan ve hiyerarşi kültürü, örgütsel yardımlaşma kültürü ölçeğinde, yönetim, kişilerarası ve kişisel yardımlaşma kültürü ve örgütsel yardımlaşma eğilimi ölçeğinde yardımlaşma eğilimi ve yardımlaşmadan kaçınma eğilimi faktörleri elde edilmiştir. SAA değişkenleri kurumlara göre değişmektedir ve bu değişkenler çalışanların yardımlaşmaya olan eğilimleri açısından göstergedir. Anahtar Sözcükler: Sağlık Yönetimi, Yardımlaşma Kültürü, Sosyal Ağ Analizi, Örgüt Kültürü, Ucinet. ABSTRACT Culture of Helping Employees in Public Health Institutions: A Study on Istanbul Provincial Health Directorate and Anatolian South Public Hospital Association Objective: To measure the level of organizational and helping culture of healthcare employees, to determine helping attributes, to make comparisons among institutions and to evaluate from a network organization point of view. Materials and Methods: Research included 751 people from the Istanbul Provincial Health Directorate, Istanbul Anatolian South Public Hospitals Association and Dr. Lütfi Kırdar Training and Research Hospital. These three institutions were included in the study because they have to take place at different levels in terms of their functions in health care provision in Istanbul and at the same time they must be institutions that are complementary to each other. Focus group interview, questionnaires and interview methods were used in the research. In the context of social network analysis, employees were requested to write down 5 people they asked for help and one person who did not request for help. The variables of the competence, accessibility, trust, sincerity and duration of acquaintance which are the helping attributes of these persons are evaluated. Results: The level of organization and helping culture of healthcare employees has been determined. The averages of helping attributes were higher among those who were not requested for help than employees who were requested for help. Among employees who were requested for help trust had the highest score and competency had the lowest score. The tendency of avoiding without help was higher among 45 years old or older, high school graduates, and 21 years or more in current institution and current position of the employees. The SAA variables of health institution employees are similar according to age, education level and years of employment. Conclusion: As a result of the research at organizational culture scale, market, clan and hierarchy culture, at organizational helping culture scale, management, interpersonal and personal helping culture and in the scale of organizational helping tendency, tendency of organizational helping and the tendency of avoiding without help have been obtained. The SAA variables vary according to institutions and these variables are indicative of the tendency of employees to help. Keywords: Health Management, Helping Culture, Social Network Analysis, Organizational Culture, Ucinet